The goals of this Core are i) to obtain, preserve, examine, diagnose, and disseminate human braint issue from autopsies of patients with Alzheimer's disease, Down's syndrome, and head injury, as well as appropriate controls; and from the resected temporal lobe specimens from patients with chronic intractable temporal lobe epilepsy; ii) to perform patient genotyping; iii) to process, embed and section animal brain tissues for immunohistochemical investigations, and to provide neuropathological evaluations of these tissues; and iv) to provide electron microscopical evaluation of tissues and cell cultures. Continued achievements of these goals will enhance and facilitate achievement of the aims of the Projects in this Program Project. In this way, this Core will facilitate investigation of glial-neuronal relationships underlying early pathogenic events in the development of the neuropathological features of Alzheimer's disease.